JP2000244300A - On and off detecting circuit - Google Patents
On and off detecting circuitInfo
- Publication number
- JP2000244300A JP2000244300A JP11043372A JP4337299A JP2000244300A JP 2000244300 A JP2000244300 A JP 2000244300A JP 11043372 A JP11043372 A JP 11043372A JP 4337299 A JP4337299 A JP 4337299A JP 2000244300 A JP2000244300 A JP 2000244300A
- Authority
- JP
- Japan
- Prior art keywords
- semiconductor switch
- switch
- voltage
- parallel
- detector
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、数値制御装置など
の外部に接続された半導体スイッチのオンオフ状態を数
値制御装置などの内部論理回路に伝達する回路の改良に
関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a circuit for transmitting an on / off state of a semiconductor switch connected to an external device such as a numerical control device to an internal logic circuit such as a numerical control device.
【０００２】[0002]
【従来の技術】従来のオンオフ検出方法について図にお
いて説明する。図２は従来のオンオフ検出回路を示す図
である。同図において９は電流制限抵抗、１０はフォト
カプラ、１１は外部電源、１２はスイッチ、内部は数値
制御装置等の内部、外部は数値制御装置等の外部を示
す。数値制御装置などの外部に接続されたスイッチ１２
がオンオフすることにより、外部電源１１から電流制限
抵抗９を介しフォトカプラ１０をオンオフさせる。2. Description of the Related Art A conventional on / off detection method will be described with reference to the drawings. FIG. 2 is a diagram showing a conventional on / off detection circuit. In the figure, 9 is a current limiting resistor, 10 is a photocoupler, 11 is an external power supply, 12 is a switch, the inside is the inside of a numerical control device or the like, and the outside is the outside of a numerical control device or the like. Externally connected switch 12 such as a numerical controller
Is turned on and off, the photocoupler 10 is turned on and off from the external power supply 11 via the current limiting resistor 9.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、図２に
おいて、スイッチ１２に半導体スイッチ（たとえばソリ
ッドステートリレー）を使用した場合、その漏れ電流に
よりフォトカプラ１０がオンしてしまうことがあった。
半導体スイッチは一次側に流れる電流の大小によって、
その二次側の半導体がオンオフするが、この二次側の半
導体がオフ状態にあっても漏れ電流が流れるからであ
る。本発明の目的は、漏れ電流の影響を受けにくい安価
なオンオフ検出回路を提供することにある。However, in FIG. 2, when a semiconductor switch (for example, a solid state relay) is used as the switch 12, the photocoupler 10 may be turned on due to the leakage current.
The semiconductor switch depends on the magnitude of the current flowing to the primary side,
This is because the semiconductor on the secondary side turns on and off, but leakage current flows even when the semiconductor on the secondary side is in the off state. An object of the present invention is to provide an inexpensive on / off detection circuit that is less affected by leakage current.
【０００４】[0004]
【課題を解決するための手段】上記の問題を解決するた
め、本発明は、制御装置の外部に接続された半導体スイ
ッチのオンオフをこの制御装置の内部で検出するように
したオンオフ検出回路において、前記半導体スイッチに
並列接続され、前記半導体スイッチのオンオフしきい値
を決定するための分圧抵抗の直列体と、この分圧抵抗の
接続点の電圧により、前記半導体スイッチのオンオフ状
態を検出する検出器と、前記直列体と前記半導体スイッ
チの並列体に直列接続され、前記半導体スイッチに流れ
る電流を制限する電流制限抵抗と、前記半導体スイッチ
のオンオフ状態を伝達するためのフォトカプラと前記検
出器との直列体が、前記制限抵抗と分圧抵抗との直列体
に並列接続されたことを特徴とするオンオフ検出回路を
提供するものである。In order to solve the above problem, the present invention relates to an on / off detection circuit for detecting the on / off of a semiconductor switch connected to the outside of a control device inside the control device. A series connection of a voltage dividing resistor connected in parallel to the semiconductor switch for determining an on / off threshold value of the semiconductor switch, and a detection for detecting an on / off state of the semiconductor switch by a voltage at a connection point of the voltage dividing resistor. A current limiting resistor connected in series to the series body and the parallel body of the semiconductor switch to limit a current flowing through the semiconductor switch; a photocoupler for transmitting an on / off state of the semiconductor switch; and the detector. Is connected in parallel to the series body of the limiting resistor and the voltage dividing resistor. .
【０００５】[0005]
【発明の実施の形態】本発明の実施の形態を、図を参照
して説明する。図１は本発明の一実施例を示す回路図で
ある。１、４は電流制限抵抗、２はフォトカプラ、３は
検出器、５、６は分圧抵抗、７は半導体スイッチ（以下
単にスイッチという）、８は外部電源である。ここで、
分圧抵抗５、６にかかる電圧が検出器の検出電圧を上回
るように、外部電源８の電圧を設定しておく。そうする
ことによって、電圧検出器３がオン状態となり、フォト
カプラ２がオン状態になる。スイッチ７がオンしていな
い状態では、漏れ電流が電流制限抵抗４を経由してスイ
ッチ７に流れ、電流制限抵抗４に電圧降下が発生する。
しかしながら、分圧抵抗５、６の接続点にかかる電圧が
検出器３の検出電圧以下にならない限り電圧検出器はオ
ンのままであり、フォトカプラ２はオンのままとなる。
ここで、スイッチ７をオンすると、外部電源８より電流
制限抵抗４によって制限された電流がスイッチ７に流
れ、電流制限抵抗４に電圧降下が発生する。この電圧降
下はスイッチ７がオンしていない状態に比べて大きくな
り、その結果、分圧抵抗５、６間の電圧が電圧検出器３
の検出電圧以下になるため、電圧検出器３がオフ状態と
なり、フォトカプラ２がオフ状態となる。ここで、スイ
ッチ７がオフ状態の時に、スイッチ７の漏れ電流による
電流制限抵抗４の電圧降下があっても、分圧抵抗５、６
で構成される電圧が電圧検出器３の検出電圧を越えるよ
う、電流制限抵抗４の値もしくは外部電源８の電圧を設
定する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a circuit diagram showing one embodiment of the present invention. 1, 4 are current limiting resistors, 2 is a photocoupler, 3 is a detector, 5 and 6 are voltage dividing resistors, 7 is a semiconductor switch (hereinafter simply referred to as a switch), and 8 is an external power supply. here,
The voltage of the external power supply 8 is set so that the voltage applied to the voltage dividing resistors 5 and 6 exceeds the detection voltage of the detector. By doing so, the voltage detector 3 is turned on, and the photocoupler 2 is turned on. When the switch 7 is not turned on, a leakage current flows through the switch 7 via the current limiting resistor 4, and a voltage drop occurs in the current limiting resistor 4.
However, as long as the voltage applied to the connection point between the voltage dividing resistors 5 and 6 does not become lower than the detection voltage of the detector 3, the voltage detector remains on and the photocoupler 2 remains on.
Here, when the switch 7 is turned on, a current limited by the current limiting resistor 4 flows from the external power supply 8 to the switch 7, and a voltage drop occurs in the current limiting resistor 4. This voltage drop is greater than in the state where the switch 7 is not turned on. As a result, the voltage between the voltage dividing resistors 5 and 6 is
, The voltage detector 3 is turned off, and the photocoupler 2 is turned off. Here, when the switch 7 is off, even if there is a voltage drop of the current limiting resistor 4 due to the leakage current of the switch 7, the voltage dividing resistors 5, 6
The value of the current limiting resistor 4 or the voltage of the external power supply 8 is set so that the voltage constituted by
【０００６】[0006]
【発明の効果】本発明により、半導体スイッチのオンオ
フ検出レベルを規定でき、半導体スイッチの漏れ電流の
影響を受けにくいオンオフ検出回路の構成が可能とな
る。According to the present invention, the ON / OFF detection level of the semiconductor switch can be specified, and an ON / OFF detection circuit which is hardly affected by the leakage current of the semiconductor switch can be realized.
【図１】本発明の実施例のオンオフ検出回路の構成。FIG. 1 is a configuration of an on / off detection circuit according to an embodiment of the present invention.
【図２】従来のオンオフ検出回路の構成。FIG. 2 is a configuration of a conventional on / off detection circuit.
１、４、９ 電流制限抵抗 ２、１０ フォトカプラ ３ 検出器 ５、６ 分圧抵抗 ７、１２ スイッチ ８、１１ 外部電源 1, 4, 9 Current limiting resistor 2, 10 Photocoupler 3 Detector 5, 6 Voltage dividing resistor 7, 12 Switch 8, 11 External power supply
Claims (1)
ッチのオンオフをこの制御装置の内部で検出するように
したオンオフ検出回路において、前記半導体スイッチに
並列接続され、前記半導体スイッチのオンオフしきい値
を決定するための分圧抵抗の直列体と、この分圧抵抗の
接続点の電圧により、前記半導体スイッチのオンオフ状
態を検出する検出器と、前記直列体と前記半導体スイッ
チの並列体に直列接続され、前記半導体スイッチに流れ
る電流を制限する電流制限抵抗と、前記半導体スイッチ
のオンオフ状態を伝達するためのフォトカプラと前記検
出器との直列体が、前記制限抵抗と分圧抵抗との直列体
に並列接続されたことを特徴とするオンオフ検出回路。An on / off detection circuit for detecting on / off of a semiconductor switch connected to the outside of a control device inside the control device, wherein the on / off threshold value of the semiconductor switch is connected in parallel to the semiconductor switch. And a detector for detecting the ON / OFF state of the semiconductor switch by a voltage at a connection point of the voltage dividing resistor, and a series connection of the series body and the parallel body of the semiconductor switch. A current limiting resistor for limiting a current flowing through the semiconductor switch, a series body of a photocoupler for transmitting an on / off state of the semiconductor switch and the detector, and a series body of the limiting resistor and a voltage dividing resistor. An on / off detection circuit, which is connected in parallel to the circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11043372A JP2000244300A (en) | 1999-02-22 | 1999-02-22 | On and off detecting circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11043372A JP2000244300A (en) | 1999-02-22 | 1999-02-22 | On and off detecting circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2000244300A true JP2000244300A (en) | 2000-09-08 |
Family
ID=12662024
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11043372A Pending JP2000244300A (en) | 1999-02-22 | 1999-02-22 | On and off detecting circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2000244300A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107834631A (en) * | 2017-11-09 | 2018-03-23 | 常州格力博有限公司 | Anti- battery static leakage circuit |
-
1999
- 1999-02-22 JP JP11043372A patent/JP2000244300A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107834631A (en) * | 2017-11-09 | 2018-03-23 | 常州格力博有限公司 | Anti- battery static leakage circuit |
| CN107834631B (en) * | 2017-11-09 | 2021-01-19 | 格力博(江苏)股份有限公司 | Circuit for preventing static electricity leakage of battery |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2006105603A (en) | Method and circuit for detecting overcurrent | |
| US9960588B2 (en) | Power switch device | |
| CN112526337A (en) | Electric vehicle relay adhesion detection circuit and detection method thereof | |
| JP2000244300A (en) | On and off detecting circuit | |
| JP5429439B2 (en) | Current limiting device | |
| JP2001022452A (en) | Source voltage stepping-down circuit | |
| JP2013026769A (en) | Device for controlling switching element | |
| JP2003189598A (en) | Switching power unit | |
| JP2000013991A (en) | Method and circuit for limiting overcurrent using mosfet switch | |
| JPH0923644A (en) | Switching power supply | |
| JPH04238272A (en) | Power supply circuit with leakage current detecting function | |
| JP2007006615A (en) | Fault detection circuit | |
| JP4543973B2 (en) | AS-i slave overload / short-circuit protection circuit | |
| JP5370915B2 (en) | Voltage limiting circuit | |
| JP2008099356A (en) | Mode switching circuit | |
| US6408071B1 (en) | Modem line connection circuit and the control circuit | |
| JP4061947B2 (en) | Printer | |
| JPH0758894B2 (en) | Electric circuit device | |
| JP2003270275A (en) | Current detection circuit | |
| JP2024030901A (en) | voltage monitoring circuit | |
| JPH06331677A (en) | Load fault diagnostic circuit | |
| JPH08292806A (en) | Input circuit of control unit | |
| JPH07264027A (en) | Contact reader | |
| JPH03195212A (en) | Semiconductor device | |
| JP3199550B2 (en) | Battery check circuit |